A century ago today, the Balkan wars began. On Oct. 8, 1912, the tiny Kingdom of Montenegro declared war on the weak Ottoman Empire, launching an invasion of Albania, then under nominal Turkish rule. Three other Balkan states in league with the Montenegrins — Bulgaria, Greece and Serbia — rapidly followed suit, waging war on the old imperial enemy while drawing upon a wellspring of national sentiment in each of their homelands. By March 1913, their blood-soaked campaigns had effectively pushed the enfeebled Ottomans out of Europe. Yet by July, Greece and Serbia would clash with Bulgaria in what’s known as the Second Balkan War — a bitter monthlong struggle that saw more territory change hands, more villages razed and more bodies dumped into the earth.

The peace that followed was no peace at all. A year later, with Europe’s great powers entwined in the fate of the Balkans, a Yugoslav nationalist in the Bosnian city of Sarajevo killed the crown prince of the Austro-Hungarian Empire. Europe plunged into World War I.

“The Balkans,” goes one of the many witticisms attributed to Winston Churchill, “generates more history than it can locally consume.” To Churchill and many Western observers of his era, this rugged stretch of southeastern Europe was a headache, a geopolitical mess that had for centuries been at the crossroads of empires and religions, riven by ethnic tribalisms and the meddling of outside powers. Half a century earlier, Prussian Chancellor Otto von Bismarck — the architect of the modern German state — expressed his disgust with this nuisance of a region, scoffing that the whole of the Balkans was “not worth the bones of one Pomeranian grenadier” in his employ.

But while these grand statesmen of the West saw a backward land brimming with ancient hatreds, the Balkans’ turbulent past, and the legacy of the Balkan wars in particular, perhaps offers a more instructive history lesson for our present than even World War I. This is not just because the Balkan wars spawned some historic firsts on the battlefield — such as the first instance when aircraft was used to attack an enemy (by the Bulgarians) or some of the first grim scenes of trench warfare in continental Europe (observers recount how, in one trench, the legs of dead Turkish soldiers froze into the ground and had to be hacked off). It’s because in many ways these battles fought a century ago reflect our world today: one where internecine and sectarian conflicts — in, say, Syria or the Democratic Republic of Congo — are enmeshed in the agendas of outside powers and where the trauma of that violence often augurs more of the same.

On the surface, the Balkan wars were opportunistic land grabs. The Ottoman Empire, at this point very much “the sick man of Europe,” had held sway over a vast swath of the region since the 15th century, but by the 19th century was a steadily hemorrhaging territory. Newly independent states in Bulgaria, Greece and Serbia — at times, egged on, at others, reined in by imperial powers like Russia, Austria-Hungary, Germany and the U.K., who were all jockeying for supremacy— were now possessed by their own fantasies of creating a Greater Serbia or Greater Bulgaria. The genie of ethnic nationalism was very much out of its bottle, and the Balkans were suffused with anti-Turkish, anti-Muslim feeling. See these popular lines of doggerel, penned by a mid-19th century Montenegrin prince:

So tear down minarets and mosques,

and the kindle the Serbian yule logs,

and let us paint our Easter eggs …

… our faiths will be submerged in blood.

The better of the two will be rise redeemed.

[Eid] can never live in peace

with Christmas Day.

And there was blood. The joint Balkan invasion of Turkish territory in Albania, Macedonia and Thrace, along the rim of the Aegean Sea, saw brutal, bitter fighting, miserable sieges and myriad atrocities committed on all sides. A Czech correspondent described the approach to Lozengrad, the Bulgarian name for what’s now Kirklareli, Turkey, as something out of Dante’s Inferno. “Only his dark genius could recreate all the horrors of the cold swamps out of which stick the twisted and mutilated bodies of the fallen,” he wrote in the Czech daily Pravo Lidu in October 1912. Another journalist entering the city of Adrianople (now Edirne, Turkey) when it was finally surrendered by the Ottomans to the Bulgarians in March 1913, recounted the utter desolation of the ancient town, then a “ghastly theater of blood”: “Everywhere bodies reduced to mere bones, blue hands ripped from forearms, the bizarre gestures, empty eye-sockets, open mouths as if calling in desperation, the shattered teeth behind the torn and blackened lips.”

The capture of Adrianople effectively brought what’s considered the First Balkan War to a close. A treaty brokered in London by Europe’s great powers ended hostilities by May, but would soon unravel when, in late June, territorial disputes led to the Greeks and Serbs turning on the Bulgarians — the biggest victors of the First Balkan War — and, even at times with the help of Turkish fighters, stripping the Bulgarians of much of the gains they had made in the earlier conflict. It was a huge source of national humiliation for the Bulgarians, who had mobilized 500,000 troops — a quarter of their entire male population — during the wars.

In all, over the course of the Balkan wars, some 200,000 soldiers died in less than a year with countless numbers of civilians massacred in raids on towns or laid low by starvation and disease. Grisly accounts followed one after the other of pogroms and ethnic cleansing in a dizzyingly complex, diverse part of the world that, for all the inefficiencies and injustices of Ottoman rule, had existed in relative multicultural harmony for centuries. A landmark report on the Balkan wars, issued in 1913 by the then brand new Carnegie Endowment for International Peace in Washington, D.C., claimed that “there is no clause in international law applicable to land war and to the treatment of the wounded, which was not violated … by all the belligerents.” The Carnegie report went on to declaim “the megalomania of the national ideal” — the ugly, crude nationalism that fired the expansionist zeal of countries the world over. “Violence carries its own punishment with it and something very different from armed force will be needed to establish order and peace in the Balkans,” the report warns.

But that was a message, like many others made then by dovish liberals and peaceniks, that went unheeded. At a time when the great powers were steadily amassing arms and tying themselves into alliances primed for war, the smaller Balkan states could only end up pawns in a much bigger game of chess. Resurgent Serbian nationalism, backed by Russia, put the two ultimately at odds with Austria-Hungary, triggering World War I. “The Balkans were not the powder keg, as is so often believed: the metaphor is inaccurate,” writes journalist and Balkans historian Misha Glenny, in his book, The Balkans: Nationalism, War and the Great Powers, 1804-1999. “They were merely the powder trail that the great powers themselves had laid. The powder keg was Europe.”

What followed, of course, involved more bloodshed, more seismic upheavals, more redrawing of maps. Decades later, the Balkans tragically convulsed in another round of ethnic warfare following the collapse of the Soviet Union and the fall of Yugoslavia’s own communist state. As some commentators parroted Churchill and Bismarck’s dismay with the region, Mark Mazower, a noted scholar of Eastern Europe now at Columbia University, wrote in an essay how the fragile politics of a nation — not simply old ethnic enmities — can lead to the disintegration of once tolerant, integrated societies: “It has been war — first as a specter then as a reality — which affected people’s sense of ethnic identity.”

Looking at the vicious sectarian fighting taking place now in Syria, one wonders what sort of country can possibly emerge when the shooting stops. The hideous excesses 0f an authoritarian regime, the cash and weaponry supplied to rebels by foreign powers and the unraveling of the delicate political consensus that once existed has led to a grinding, miserable civil war with no end in sight.

Prescient for its time, the 1913 Carnegie report opens with an impassioned appeal for peace and an end to the “monstrous business” of the arms race. Otherwise, the legacy of the Balkan wars was clear:

[It will be] only the beginning of other wars, or rather of a continuous war, the worst of all, a war of religion, of reprisals, of race, a war of one people against another, of man against man and brother against brother. It has become a competition, as to who can best dispossess and “denationalize” his neighbor.

Violence, as the report says, is its own punishment. And a century doesn’t seem so long ago.